1. Field of the Invention
The present invention relates to a shielding terminal to be connected with an end of a shielded cable and to a method for connecting a shielding terminal with an end of a shielded cable.
2. Description of the Related Art
A known shielding terminal is shown in FIGS. 18 and 19. The known shielding terminal comprises an inner terminal xe2x80x9caxe2x80x9d to be connected with a mating terminal, a dielectric element xe2x80x9cbxe2x80x9d for accommodating the inner terminal xe2x80x9caxe2x80x9d, and an outer terminal xe2x80x9ccxe2x80x9d in the form of a rectangular tube for accommodating the dielectric element xe2x80x9cbxe2x80x9d. The inner terminal xe2x80x9caxe2x80x9d includes a core-fastening portion xe2x80x9chxe2x80x9d that is crimped into connection with an end of a core xe2x80x9cexe2x80x9d of a shielded cable xe2x80x9cdxe2x80x9d. The outer terminal includes a braided wire fastening portion xe2x80x9cixe2x80x9d and a sheath fastening portion xe2x80x9cjxe2x80x9d that are crimped into connection with an end of a braided wire xe2x80x9cfxe2x80x9d and an end of a sheath xe2x80x9cgxe2x80x9d, respectively.
A terminal mounting apparatus is employed for simultaneously connecting the core xe2x80x9cexe2x80x9d, the braided wire xe2x80x9cfxe2x80x9d and the sheath xe2x80x9cgxe2x80x9d. The apparatus requires windows xe2x80x9ckxe2x80x9d to be formed in the upper and lower surfaces of the outer terminal xe2x80x9ccxe2x80x9d so that the apparatus can access and crimp the core fastening portion xe2x80x9chxe2x80x9d of the inner terminal xe2x80x9caxe2x80x9d that is accommodated in the outer terminal xe2x80x9ccxe2x80x9d. The requirement for windows means that the portion of the shielding terminal that is fastened to the core xe2x80x9cexe2x80x9d has its upper and lower surfaces exposed through the windows xe2x80x9ckxe2x80x9d. As a result, shielding characteristics, such as a radiation characteristic, are undesirably reduced.
In view of the above problem, an object of the present invention is to provide a shielding terminal and a connection method for improving shielding characteristics.
The subject invention is directed to a shielding terminal for connection with an end of a shielded cable. The cable comprises a core provided substantially in the center of the cable. An insulating layer surrounds the core, and a shield layer, preferably a braided wire, coaxially surrounds the insulating layer. A sheath then surrounds the braided wire.
The shielding terminal comprises an inner terminal to be connected with the core, and a dielectric element for at least partly accommodating the inner terminal. An outer terminal at least partly accommodates the dielectric element and can be connected with the shield layer or braided wire. The shielding terminal further comprises a cover having a covering portion for substantially covering an open space around a section of the inner terminal connected with the core, and at least one mount portion mountable on a section of the outer terminal that can be connected with the shield layer or braided wire. At least one assembling piece is arranged substantially along a sidewall of the outer terminal, and is formed with at least one displacement-restricting portion for restricting a displacement of the cover.
The cover covers the open space that exists around sections of the inner terminal that are fastened to the core. As a result, shielding characteristics, such as a radiation characteristic, can be improved. The cover is mountable on the connected section of the outer terminal. Consequently, the shielding terminal can be simplified, and does not require a separate mounting structure. Further, the displacement-restricting portion restricts displacement of the cover.
According to a preferred embodiment of the invention, the assembling piece extends from the covering portion of the cover.
Preferably, the displacement-restricting portion restricts displacement of the cover by being held substantially in contact with a connecting wall that connects the sidewalls of the outer terminal. The connecting wall preferably is a bottom wall of the outer terminal. Accordingly, downward displacement of the cover inside the outer terminal can be restricted.
Each displacement-restricting portion preferably comprises a first displacement-restricting portion that is held in contact with the sidewall of the outer terminal and a second displacement-restricting portion that is held in contact with the connecting wall.
The displacement-restricting portion preferably is inserted between the sidewall of the outer terminal and a sidewall of the dielectric element. Thus the displacement restricting portion prevents the assembling piece from being bent inward of the outer terminal.
The displacement-restricting portion prevents the assembling piece from being bent inward of the outer terminal by being inserted between the sidewall of the outer terminal and a sidewall of the dielectric element. Accordingly, the displacement restricting portion prevents the assembling piece from being bent inward of the outer terminal.
Most preferably, the mount portions comprise a clip-lock construction.
According to the invention, there is further provided a method for connecting a shielding terminal with an end of a shielded cable. The shielded cable comprises a core substantially in the center of the cable. An insulating layer surrounds the core, a shield layer coaxially surrounds the insulating layer, and a sheath surrounds the shield layer. The method comprises connecting an inner terminal with the core and at least partly accommodating the inner terminal in a dielectric element. The method continues by at least partly accommodating the dielectric element in an outer terminal and connecting the outer terminal with the shield layer. The method then includes substantially covering an open space around a section of the inner terminal connected with the core by means of a cover having a covering portion. The covering step comprises mounting at least one mount portion of the cover on a section of the outer terminal that is connected with the shield layer, and arranging at least one assembling piece substantially along a sidewall of the outer terminal for restricting a displacement of the cover.
According to a preferred embodiment of the invention, the covering step further comprises bringing at least one displacement-restricting portion into contact with a connecting wall that connects the side walls of the outer terminal. The connecting wall preferably is a bottom wall of the outer terminal.
These and other objects, features and advantages of the present invention will become more apparent upon a reading of the following detailed description and accompanying drawings.